Problem with HO alt. Help!

I bought a 240A alternator from Iraggi a few months ago and just got around to having it installed about 2 weeks ago. A Hawker Odyssey battery and the big 3 was done with 1/0 gauge as well. The amplifiers are a Tsunami db1800t and Cadence Z8000 (total RMS = roughly 2100w), although it shouldn't be drawing full wattage constantly for music.

When I drive at night, my lights still dim a decent amount, even when the RPMs are 1800+. Honestly, I'm a little disappointed after having spent $500 to upgrade the electrical system. I know amps aren't 100% efficient and can draw a lot of amperage, but it doesn't seem like the HO alt. is making a big difference over the stock 130A alternator. Is there any way I can test the output of the alternator to ensure it's doing the job right?

Re: Problem with HO alt. Help!

Where can I get it benched? Every place I see only tests voltage, not amperage. I'm not an electrical expert, I just heard "HO Alt this, HO Alt that" and wanted to get it done right the first time, rather than doing something else and having problems down the line and spending even more money.